Vaisala WS425 - Manual (Page 51)

Chapter 4 ________________________________________________________________ Operation
VAISALA _______________________________________________________________________ 51
Resume Operation
After opening the configuration menu, return to the current mode of
operation by selecting "Resume Operation". This selection terminates the
configuration dialog.
NOTE Changes to the configuration will not be saved automatically. Use the
SAVE CONFIGURATION command to save the changes.
SDI-12 Protocol
SDI-12 is a standard for interfacing data recorders with microprocessor-
based sensors. The name stands for serial/digital interface at 1200 baud.
SDI-12 is intended for applications with the following requirements:
- Battery-powered operation with minimal current drain.
- Low system cost.
- Use of a single data recorder with multiple sensors on one cable.
- Up to 200 feet (60 meters) of cable between a sensor and a data
recorder.
SDI-12 Support Group
The SDI-12 Support Group is an association of companies that produce
and use SDI-12 products with the purpose of reviewing requests to
enhance, clarify, or modify the
SDI-12 architecture and that votes on proposed changes to SDI-12. More
information of the group, as well as the complete SDI-12 standard text is
available from the SDI-12 web-site in the following address: www.sdi-
12.org/.
SDI-12 Electrical Interface
The SDI-12 electrical interface uses the SDI-12 bus to transmit serial
data between SDI-12 data recorders and sensors. The SDI-12 bus is the
cable that connects multiple SDI-12 devices. This is a cable with three
conductors:
- A serial data line
- A ground line
- A 12-volt line